My long delayed ER18 MTM (still in progress)

[WiseG]

good looking

 

[WiseG]

I am looking forward to show you my build

 

[capricious]

Sure ... what did you get - ribbon or dome version?

 

[capricious]

So finally i got around to playing with it. I moved them from the living room with hard floors and open ceiling to my study which is carpeted and much smaller (11x12). The difference was night and day! Suddenly the highs and mids that were recessed were more prominent and the bass that was overly powerful seemed to be a bit more under control.

I think the bass was overwhelming everything else downstairs and that gave me the impression that mids/highs were recessed. Goes to show that room is probably your most important part of the audio chain. Get that right and you'll be able to fully enjoy your system.

I'm listening to natalie merchant as i'm typing this, and can only marvel at how she sounds through these speakers. This speaker has a top to bottom coherence that i've not heard before. I love my selah SSRs, but they are small bookshelf that have little bass. This has a honest mid 30s response, and is an extremely smooth sounding speaker. Imaging is pinpoint, and sound is very well layered.I'm driving them with a hybrid integrated amplifier - Yaqin VK-2100.

Highly recommended speaker. Thanks to Paul K and Dennis for creating this wonderful speaker.

 

[mattsk8]

That's awesome and I totally get what you're saying. These might be the most finicky speakers I've ever owned as far as room treatments are concerned! It's amazing how much placement changes the sound of these.

If you like Natalie Merchant, try Mazzy Star's Blue Light on them. Just relax in your chair and wait for the guitar in the middle !

Nice job on your cabinets btw; they look incredible!

 

[doors666]

capricious, in post 14, arent the left and right speakers switched. I thought the tweeters are supposed to be on the outer sides. How is it for the rs28 domes?

Quick question, the base is larger than the speaker by about 3.5" in depth, how is it divided, equal for front and back, 1.75"?

 

[capricious]

capricious, in post 14, arent the left and right speakers switched. I thought the tweeters are supposed to be on the outer sides. How is it for the rs28 domes?

Quick question, the base is larger than the speaker by about 3.5" in depth, how is it divided, equal for front and back, 1.75"?

From what i read someplace long back, u want the tweeters on the inside if the room is small, and on the outside if it is placed in a larger room.
As for the base, i centered the speaker on it.

 

[Swerd]

capricious, in post 14, arent the left and right speakers switched. I thought the tweeters are supposed to be on the outer sides. How is it for the rs28 domes?

There is no right or wrong for this.

If tweeters are centered on the front baffle, there usually are some small peaks in the treble range, roughly 5-8 kHz. They're caused by diffraction of high frequency sound interacting with the front edges of the cabinet. If the tweeter is centered, the distance from tweeter to both side edges are the same, and any diffraction peaks resulting from that will add together to a bigger peak. If you place the tweeter off-center, as in the ER18 MTM, the tweeter to cabinet edge distances are all different, and you minimize the size those small peaks.

All that is about a single speaker in mono. With two speakers with off-set tweeters, I wonder if anyone has listened with their speakers arranged both ways and heard a difference. I've never bothered with mine (the tweeters are closer to each other). It might depend on how far apart the towers sit.

Quick question, the base is larger than the speaker by about 3.5" in depth, how is it divided, equal for front and back, 1.75"?

I think it should be longer in the back, and equal on the sides and front. But this is DIY, you can do as you wish.

 

[doors666]

thanx guys, i will go with longer in the back.

are wood screws good enough for mounting drivers, or do i need to go for nuts.

cabs are almost finished, I havent thought of finish yet. is it possible/good idea to venner them now. do you guys first cut the driver holes and then veneer or first veneer and then cut the holes. is it going to be a pain to do this now. if yes, i will go with paint.

 

[Swerd]

are wood screws good enough for mounting drivers, or do i need to go for nuts.

The ER18 woofers have 6 screw holes and wood screws easily hold them. I use #8×¾" pan head wood screws to mount almost all drivers. Some tweeters have screw holes too small for #8 screws and I use #6 screws instead. I always pre-drill the screw holes with a drill bit slightly smaller diameter than the wood screw's threads.

I would use screw nuts or other kinds of threaded inserts only for drivers much larger and heavier than the ER18, such as sub woofers. They require drilling the all holes perpendicular to the front baffle, or the last bolt you drive in won't thread in properly. It can be very hard to do that with a hand held drill. A drill press does this much better.

cabs are almost finished, I havent thought of finish yet. is it possible/good idea to venner them now. do you guys first cut the driver holes and then veneer or first veneer and then cut the holes. is it going to be a pain to do this now. if yes, i will go with paint.

People have done this both ways. It depends on what router bits you have.

I veneer first and then cut the driver holes the same way I showed in the MB27 build thread. You always have to sand the veneer before finishing, so any marks left by rotating the circle jig will be fixed by that.

I have seen others who first cut out the driver holes including the recess for flush mounting. Later they apply veneer, covering the driver cutouts.

Once the veneer is applied, they cut a small hole with a utility knife in the center of each driver cutout and used a flush trim bit to trim the veneer around each driver hole. This will leave the veneer overhanging the flange.

Change the flush trim bit to a rabbet bit, with the same overhang as you used to cut the flange (or recess) for the driver.

Set the depth on the router to about half (or less) of the depth of the original recess that you cut for flush mounting the driver. Insert the router into the driver cutout hole and follow the circle around the hole to trim the veneer. If done properly, none of the MDF will be affected at all. With a little sanding, you should get an excellent, smooth flush trimmed veneer around the hole.

Do this in 2 separate steps, flush trim bit followed by rabbet bit. People who tried doing it in one step with the rabbet bit said it was too easy to mess it up.

Both methods work but need different router bits.

 

[mattsk8]

capricious, in post 14, arent the left and right speakers switched. I thought the tweeters are supposed to be on the outer sides. How is it for the rs28 domes?

Quick question, the base is larger than the speaker by about 3.5" in depth, how is it divided, equal for front and back, 1.75"?

Swerd's the man, so I hate to digress on this; but wouldn't it be better to go bigger on the sides and front w/ the base and be flush w/ the back? Mainly because the drivers are mounted in the front, plus the way the baffle extends 3/4" out, makes them a bit front heavy. and adding the extra 3/4" width on each side also makes them less tipsy.

This is how I made mine. Thats a pic of the front and side. The base is (basically) flush on the back.

thanx guys, i will go with longer in the back.

are wood screws good enough for mounting drivers, or do i need to go for nuts.

cabs are almost finished, I havent thought of finish yet. is it possible/good idea to venner them now. do you guys first cut the driver holes and then veneer or first veneer and then cut the holes. is it going to be a pain to do this now. if yes, i will go with paint.

As far as using threaded inserts or woodscrews go, I think it doesn't really matter as well. Although, if you're using the ribbon tweet you'll have limited option for error. You'll see when you cut out for the ribbon that you'll have small ears to screw into. I used threaded inserts for all of the drivers in mine; and the main reason is I've had issues w/ repeated removal of drivers blowing out the MDF while using woodscrews; which could be a real pia if you did that to one the MDF ears where the ribbon tweet mounts.

That said, if you're using the dome tweet maybe there's more room for error. If you do use wood screws, dip the tips of your screws into woodglue before you thread them in; that'll make the MDF less likely to blow out. The woodglue does 2 things, it lubricates the screw while youre driving it in, plus once the glue hardens it gives a firm area if you ever remove them. Just my $.02.

 

[Swerd]

Swerd's the man…

duly noted .

but wouldn't it be better to go bigger on the sides and front w/ the base and be flush w/ the back? Mainly because the drivers are mounted in the front, plus the way the baffle extends 3/4" out, makes them a bit front heavy. and adding the extra 3/4" width on each side also makes them less tipsy.

As long as you come up with an idea that works, go for it. There's no reason to do exactly what I said if your imagination is less limited than mine. I was simply copying what Jim Salk does with his tower cabinets.

Matt – I think your idea for the cabinet base is very good.

As far as using threaded inserts or woodscrews go, I think it doesn't really matter as well. Although, if you're using the ribbon tweet you'll have limited option for error. You'll see when you cut out for the ribbon that you'll have small ears to screw into. I used threaded inserts for all of the drivers in mine; and the main reason is I've had issues w/ repeated removal of drivers blowing out the MDF while using woodscrews; which could be a real pia if you did that to one the MDF ears where the ribbon tweet mounts.

That said, if you're using the dome tweet maybe there's more room for error. If you do use wood screws, dip the tips of your screws into woodglue before you thread them in; that'll make the MDF less likely to blow out. The woodglue does 2 things, it lubricates the screw while youre driving it in, plus once the glue hardens it gives a firm area if you ever remove them. Just my $.02.

The wood glue tip is a nice idea. I'll have to remember that.

Matt – what technique do you use when you mount the threaded inserts? I don't have a drill press, and I've tried T nuts and Hurricane nuts, but didn't like the results I got. What threaded inserts do you use?

 

[mattsk8]

Matt – what technique do you use when you mount the threaded inserts? I don't have a drill press, and I've tried T nuts and Hurricane nuts, but didn't like the results I got. What threaded inserts do you use?

I use my drill press (cheapo from Tractor Supply, was $150 and works awesome) whenever I can to drill the holes for the inserts. I couldn't for the Statements because the screws were a bit too deep on the face of the baffle, my press didn't go deep enough; for those I used a cordless drill, which actually works very well. The biggest key is a good, brad point wood drill bit and a steady, straight hand.

As far as threading them in, I use a set of allen wrenches (the style that flip out). I put a lot of down pressure on the allen while I'm threading them in and thread them in fairly tight. I also coat the inserts w/ woodglue before threading those in for the same reasons as the woodscrews.

Whether hand drill or drill press, I've had really good results so far. The key is very accurate measurements. It would really suck to install a threaded insert and be off a bit; although you can fix that w/ a dowel and woodglue as well. I also test fit the drivers in the baffles before I glue the cabinets up; mainly because you're kind of past the point of no return if you glue the cabinet up and one of the inserts is in wrong, since they're threaded in from the inside of the cabinet.

As far as what kind I use goes, I've tried 3 styles- the brass ones w/ no head (just an insert), the hurricane nuts, and the threaded aluminum ones that Meniscus uses. They all seem to work as long as you use woodglue when you thread them in; but the most cumbersom ones to install are the brass ones, and the ones that would seem to have a problem are the hurricane inserts that just press in (I used a C-clamp to install those and didn't have a problem, just seems like they'd be the most likely to loosen up for whatever reason). My favorite are definately the ones Meniscus uses, the aluminum ones that thread in and are kind of tapered. The brass ones look the most professional (if you care, they are on the back side so you really don't ever see them). As far as installing the brass ones goes, I put a bolt through a fairly wide washer then threaded the bolt all the way into the insert (a little vasoline on the bolt head will help it release once the inserts tight). I hand thread the insert all the way until the washer is seated on the surface, then take an impact and zip the bolt out of the insert. Like I said, the brass ones look the most professional and you don't have the big flange to deal w/ if you route out (or I've heard it called scallop) around the driver opening like you do for the Statements.

These are my favorites: best threaded inserts

 

[Swerd]

Thanks Matt. I'm glad you included a link for inserts you like. I've never tried them before.

Brass or steel inserts (I thought these worked better in hardwood and not MDF):

Just for the sake of education for DIY newbies, the kind of threaded inserts I have not had success with are shown below. Some one else may have a good method for using them, but not me.

T-nut (Don't be tempted to hammer it in, it will not go in straight)

Hurricane nut

 

[mattsk8]

I've never used the Tnuts before. I would certainly say they're a bad choice for MDF, I'd imagine you'd just fold over the little spikes and make a mess of the MDF. I could see how they might work in baltic birch or some softer wood though. But, given the other options I might choose differently anyhow. Thinking of baltic birch made me realize that I've never tried to use threaded inserts in ply before, only MDF. One area I could see an issue w/ that would be the potential to delaminate layers of ply while threading them in. For ply, I'd probably go the hurricane nut route and use a C-clamp to install them.

The T-nuts as well as those ones you have to pound little brad nails into; not a fan!

All that said, they are time consuming and they can be finicky to install; so don't let me come across as if I think if you use woodscrews you're doing it wrong. Everyone has their way

 

[doors666]

thanx guys, i will use the wood screws. have tried t-nuts for my 15" subwoofer, still drives me nuts whenever i have to open it.

i wont be opening the drivers often as i am using removable back. i always do that, never know when something needs a change.

I am using full double baffle, so probably a good idea to leave some more base plate at the front.

 

[mattsk8]

Good luck! Post many pics, maybe start another ER18 build thread ! Can't wait see how it turns out. Enjoy the ride

 

[capricious]

Well, i rewired my crossover and replaced the monster cable wire with another garden variety cable (acoustic research from amazon). Also i painted the baffle black. Thought it looked much better this way.

I am not sure if i'm imagining this ... but the speakers are sounding much much better. I always thought that the highs were kinda muted but with the wire change, they sound extended like what i expected a ribbon tweeter to do. Listening to "Fujiyama" CD i can attest that bass is as strong as ever. The vocals sound wonderful.

Overall, i think this is the best floorstander i've heard.

 

[Swerd]

I really like the way they turned out. Excellent work. Thanks for the pictures.